Application of the cationic emulsion of petroleum resin sizing agent in wheat straw stock

A novel cationic emulsion of petroleum resin sizing agent was prepared by modified petroleum resin. The application of the sizing agent in the wheat straw stock was discussed. Results indicated that it could be used as an effective internal sizing agent on neutral condition with calcium carbonate added as paper filler. The optimal conditions of sizing in the wheat straw stock were determined after the factors such as the pH value, the order of sizing, the dosage of aluminum sulfate, sizing agent and other chemicals were discussed. The optimal conditions were as follows: pH value 6.5, aluminum sulfate 1.5%, sizing agent 0.6%, calcium carbonate 20% and 0.3% additives of sizing agent. For the above stock, sizing effect with reverse sizing process was better than that of direct sizing process.